1. Field of the Invention
The invention relates to a new method for obtaining rasagiline mesylate free of noxious substances and to the obtained rasagiline mesylate.
2. Relevant Background
Rasagiline mesylate is an active pharmaceutical substance with an empirical formula of C12H13N.CH4O3S and a molecular weight of 267.34. Rasagiline mesylate is the international common accepted name for R-(+)-N-propargyl-1-aminoindan mesylate, which is represented in Formula I.

Rasagiline mesylate is an active substance indicated for the treatment of the signs and symptoms of idiopathic Parkinson disease as initial monotherapy and as adjunct therapy to levodopa. Rasagiline is a selective irreversible inhibitor of the B-form of monoamine oxidase enzyme (MAO-B). In the United States, rasagiline mesylate is marketed under the name Azilect™ for the treatment of early Parkinson disease.
The preparation of rasagiline mesylate is described in U.S. Pat. No. 5,532,415. In that patent, the product is obtained by treating the enantiopure rasagiline L-tartrate salt with methanesulfonic acid in isopropanol at reflux temperature.
International patent application publication No. WO 2007/061717 describes an alternative conversion of rasagiline L-tartrate to rasagiline mesylate. In particular, Example 17 of this reference describes the preparation of rasagiline mesylate by isolating rasagiline base from rasagiline tartrate, followed by treating the obtained rasagiline base with methanesulfonic acid in isopropanol at reflux temperature.